The present invention relates to a piece of furniture comprising an upper part, such as a tabletop, a cupboard or a number of seats, and a lower part comprising rails and legs, in which the rails and legs at least partly consist of tubes, and in which the legs at their upper ends comprise a tubular connecting piece fixedly connected to and forming an angle with the leg, and in which expandable assembly means are used for connecting legs and rails and for the making up of the rails, said assembly means comprising two connecting members inserted in the ends of adjacent tubes and which by means of one or more screws passed through an opening in one of the connecting members are kept pressed against the inner side of the tubes.
Tables are known, in which the rails are made up of oval tubes which are connected with the tubular connecting pieces at the upper part of the legs. In the known table two connecting pieces are welded to each of the legs, said connecting pieces being two pipe stubs perpendicular to one another and having the same cross-section as the rails. The assembly means consist of two tube pieces placed in parallel, said tubes pieces being pressed apart by means of pointed screws, the thread of which is inserted into a thread in the wall of one of the tube pieces, and the front end of which is passed through a hole in the tube wall of the second tube piece. Thus, the assembly means connect two tube ends placed end to end, and the connection is established thereby that the pointed screw, after the two tube pieces have been inserted in the ends of the rail tube and the connecting piece, respectively, is tightened until the two tube pieces have moved so far apart that they press against the inner surface of the flat-oval tubes.
Even though the assembly means in the shape of two parallelly running tubes are not resistant to torsional stress between the joined tube ends, it is still possible to build stable furniture frames provided that the rail extends along the edges of the upper part and connects the frame legs two by two. On account of the lacking resistance to torsional stress of the assembly, a bigger consumption of material should be expected than in connection with a construction fully welded together.
When the rail tubes are placed upright, they contribute very effectively to securing the tabletop against bending. If the rails are placed in the border area of the tabletop, the free height under the table will be considerably reduced, and it may therefore be difficult for those using the table to get room for their legs under the table, a problem which is particularly pronounced in connection with certain working tables, such as terminal tables and typewriter tables. With a view to avoiding said space problem it will be desirable to remove the rails from the edges of the tabletop. By thus keeping one side of the table free of a rail, the possibility will arise of forming a recess in the tabletop for use as a height-adjustable base for a computer keyboard or a typewriter.
With a view to attaining such a retracted position of the frame, the use of a table leg has been suggested, said leg being at its upper end welded together with one end of a connecting tube, which at its other end is welded together with two short tube fittings, to which frame tubes are connected by means of the assembly means mentioned above.
It has, however, turned out in practice to be difficult to establish the assembly between the connecting tube and the two short rail tubes with sufficient precision to avoid having to adjust the parts when assembling the table, the result being that the lower part of the table consisting of table legs and rails becomes awry.